Signal recording-reproduction apparatus are known which have a smaller depthwise length when in a play mode wherein signals can be recorded or reproduced than when in an eject mode wherein a tape cassette is to be removed from the apparatus as disclosed, for example, in Examined Japanese Patent Publications SHO 59-171070,SHO 60-163264 and SHO 61-296557.
FIGS. 14 and 15 show such an apparatus which comprises a main chassis 1 having a head cylinder 11, and a reel chassis 2 provided with a supply reel support 22 and a take-up reel support 21 and slidably mounted on the main chassis 1 for movement toward or away from the head cylinder 11.
FIG. 14 shows the apparatus in the eject mode, in which the reel chassis 2 is at rest at a first stop position S.sub.1, as projecting from the main chassis 1.
In response to a cassette loading start signal, a cassette loading mechanism (not shown) operates to advance the reel chassis 2 toward the head cylinder 11 to a second stop position S.sub.2 shown in FIG. 15, whereupon the reel chassis 2 is halted. At this position, the apparatus is set in the play mode.
Concurrently with the operation of the loading mechanism, tape leading guides on a known tape loading mechanism advance from the tape cassette side toward the head cylinder, whereby the magnetic tape is withdrawn from the cassette and wound around the head cylinder 11 over a predetermined angle around the center thereof.
With the above apparatus, a known swing idler mechanism 3 having an idle gear 32 swings upon a change-over between a usual reproduction mode and a rewinding reproduction mode, coupling the idle gear 32 selectively to one of the take-up reel support 21 and the supply reel support 22 to drive the selected reel support in the tape winding direction.
The idle gear 32 of the swing idler mechanism 3 is coupled to a capstan motor 12 on the main chassis 1 and is reversibly rotated by the motor.
With the above signal recording-reproduction apparatus, the cassette is unloaded by the movement of the reel chassis 2 from the second stop position S.sub.2 to the first stop position S.sub.1. Concurrently with this movement, the tape is unloaded by the retraction of the tape leading guides in a direction away from the head cylinder 11. Accordingly, there arises a need to drive one of the reel supports in the tape winding direction during the cassette unloading movement so as to wind up the tape, pulled out around the head cylinder, inside the cassette.
However, in the case of the above apparatus wherein the reel chassis 2 is slidable relative to the main chassis 1 as stated, the distance between the capstan motor 12 for driving the reel supports 21, 22 and these reel supports changes during the cassette unloading operation since the motor 12 is mounted on the main chassis 1 and the reel supports 21, 22 are mounted on the reel chassis 2.
For this reason, therefore, the idle gear 32 of the swing idler mechanism 3 needs to have a sufficiently large diameter in accordance with the amount of movement of the reel chassis so as to be operatively connectable to one of the reel supports at all times regardless of the position of the reel chassis. This makes the apparatus very large.
Unexamined Japanese Patent Publication SHO 60-163264 proposes a device wherein the reel support is driven by a pulley mechanism in place of the swing idler mechanism so that the support can be driven during the movement of the reel chassis. The proposed device nevertheless has the problem of being complex in construction, for example, because means are necessary for holding the belt under a specified tension.